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Installation instructions for Quaife ATB differential in Getrag MT 285 Transaxle
Parts you will need:
Differential carrier bearings (2 sets) NAPA part # BR35 or SKF #LM501310 and LM501349 (you will need 2 of each).
The output shaft oil seals (one of each) 36mmX58mmX11mm and 40mmX62mmX11
Ford part numbers: 2M5V-3K169-AA and 2M5V-3K169-BA
The input shaft oil seal is only available as part of the Throw out bearing assembly so if you don't want to buy one be very careful when removing and installing the bell housing section over the input shaft. Ford part number for Seal with housing 2M5V-7A564-AA
Instructions:
Drain oil from gearbox and remove from car per factory service procedure.
Remove lower torque arm bracket from gearbox.
Remove 19 torx head bolts holding gearbox case together (make sure you get them all, a couple of them are hidden in the ribs on the case) , some are inside the bell housing and some are outside the gearbox. With a suitable punch drive the 2 locating pins from the case; be careful not to damage the case by running the punch into the case.
With the bell housing facing up use a soft hammer (dead blow) to brake the case half's apart (there is a sealant holding it together) DO NOT USE A SCREWDRIVER TO PRY IT APART YOU WILL DAMAGE THE MACHINED SURFACE AND IT WILL NOT SEAL WHEN YOU PUT IT BACK TOGETHER.
Lift the bell housing off the input shaft being careful not to damage the input shaft seal. All of the gears will remain in the lower case half.
The differential carrier with crown wheel can now be lifted out of the case.
Remove the 10 bolts holding the crown wheel to the carrier. Using a soft hammer or wood block work the crown wheel off the carrier by tapping around the outer edge (it is lightly pressed onto the carrier).
Clean the Crown wheel carefully and warm to approximately 250 deg F (I use the oven, this is why you need to clean the gear, it will stink up the house if it still has any oil on it). Clean the Quaife unit and be ready to install the crown wheel quickly when you take it out of the oven. It helps to have a second pair of hands to install the gear because you have to get it on straight and get the bolt holes lined up. Start 4 of the bolts and make sure the gear is seated on the housing before it cools off and shrinks onto the Quaife housing. Remove the bolts and using RED Loctite install all bolts and torque to 61-66 ft/lbs.
Press new bearings onto Quaife housing.
Remove the output shaft oil seals from the transaxle housings. With a torch or heat gun warm the area around the differential carrier outer bearing races (have some water available and when a drop just dances off the aluminum that should be warm enough) the outer race should come out of the housing easily now. There will be shims behind the bearing race in the bell housing side of the case remove them and set them aside. Install the new outer bearing race in the lower case (the one with all the gears still in it) and make sure it is seated in the housing. Now install the outer race in the bell housing side of the case without the shims but do not seat it in the housing. Leave it at least 0.100 inch away from the seat.
Set the Quaife LSD with the crown wheel in the lower gear case and install the bell housing half. BE CAREFUL MAKE SURE NOT TO DAMAGE THE INPUT SHAFT SEAL AND MAKE SURE THE SHIFT SHAFTS SLIDE INTO THE POCKETS IN THE CASE. Secure it with the 19 bolts. Take the torch or heat gun and warm up the case around the output shaft area on the bell housing side. This will allow the bearing race to move in the housing.
Carefully remove the bell housing and measure the distance between the bearing race and the shoulder it is supposed to seat on. The shim you need is this dimension PLUS 0.006-0.010 inches this is the preload needed for the bearings. Measure the shim you removed from the case when you took it apart I have found at least 2 gearboxes that used the same shim as were installed at the factory. If you need to change the shim you can try a local Differential or transmission repair shop they often have a selection of shims and might have just what you need. Heat up the housing and remove the outer bearing race, install the shims and install the bearing. Install the output shaft seals.
Clean the mating surfaces of the gearbox case and use a light coat of Loctite 5203 sealant. Assemble the case and start all of the 19 bolts (I used blue Loctite) lightly snug 3-5 of the bolts and reinstall the dowel pins in the case. Using a cross pattern tighten the case bolts to 19-22ft/lbs.
Re install the torque arm mounting bracket.
Install the gearbox and refill with oil. I recommend the original FORD transmission fluid but have also used Red Line MTL with good success.
This thread will be sticky'd until it is submitted into the Official How-To Archive.
Installation instructions for Quaife ATB differential in Getrag MT 285 Transaxle
Parts you will need:
Differential carrier bearings (2 sets) NAPA part # BR35 or SKF #LM501310 and LM501349 (you will need 2 of each).
The output shaft oil seals (one of each) 36mmX58mmX11mm and 40mmX62mmX11
Ford part numbers: 2M5V-3K169-AA and 2M5V-3K169-BA
The input shaft oil seal is only available as part of the Throw out bearing assembly so if you don't want to buy one be very careful when removing and installing the bell housing section over the input shaft. Ford part number for Seal with housing 2M5V-7A564-AA
Instructions:
Drain oil from gearbox and remove from car per factory service procedure.
Remove lower torque arm bracket from gearbox.
Remove 19 torx head bolts holding gearbox case together (make sure you get them all, a couple of them are hidden in the ribs on the case) , some are inside the bell housing and some are outside the gearbox. With a suitable punch drive the 2 locating pins from the case; be careful not to damage the case by running the punch into the case.

With the bell housing facing up use a soft hammer (dead blow) to brake the case half's apart (there is a sealant holding it together) DO NOT USE A SCREWDRIVER TO PRY IT APART YOU WILL DAMAGE THE MACHINED SURFACE AND IT WILL NOT SEAL WHEN YOU PUT IT BACK TOGETHER.
Lift the bell housing off the input shaft being careful not to damage the input shaft seal. All of the gears will remain in the lower case half.

The differential carrier with crown wheel can now be lifted out of the case.

Remove the 10 bolts holding the crown wheel to the carrier. Using a soft hammer or wood block work the crown wheel off the carrier by tapping around the outer edge (it is lightly pressed onto the carrier).
Clean the Crown wheel carefully and warm to approximately 250 deg F (I use the oven, this is why you need to clean the gear, it will stink up the house if it still has any oil on it). Clean the Quaife unit and be ready to install the crown wheel quickly when you take it out of the oven. It helps to have a second pair of hands to install the gear because you have to get it on straight and get the bolt holes lined up. Start 4 of the bolts and make sure the gear is seated on the housing before it cools off and shrinks onto the Quaife housing. Remove the bolts and using RED Loctite install all bolts and torque to 61-66 ft/lbs.

Press new bearings onto Quaife housing.
Remove the output shaft oil seals from the transaxle housings. With a torch or heat gun warm the area around the differential carrier outer bearing races (have some water available and when a drop just dances off the aluminum that should be warm enough) the outer race should come out of the housing easily now. There will be shims behind the bearing race in the bell housing side of the case remove them and set them aside. Install the new outer bearing race in the lower case (the one with all the gears still in it) and make sure it is seated in the housing. Now install the outer race in the bell housing side of the case without the shims but do not seat it in the housing. Leave it at least 0.100 inch away from the seat.

Set the Quaife LSD with the crown wheel in the lower gear case and install the bell housing half. BE CAREFUL MAKE SURE NOT TO DAMAGE THE INPUT SHAFT SEAL AND MAKE SURE THE SHIFT SHAFTS SLIDE INTO THE POCKETS IN THE CASE. Secure it with the 19 bolts. Take the torch or heat gun and warm up the case around the output shaft area on the bell housing side. This will allow the bearing race to move in the housing.
Carefully remove the bell housing and measure the distance between the bearing race and the shoulder it is supposed to seat on. The shim you need is this dimension PLUS 0.006-0.010 inches this is the preload needed for the bearings. Measure the shim you removed from the case when you took it apart I have found at least 2 gearboxes that used the same shim as were installed at the factory. If you need to change the shim you can try a local Differential or transmission repair shop they often have a selection of shims and might have just what you need. Heat up the housing and remove the outer bearing race, install the shims and install the bearing. Install the output shaft seals.
Clean the mating surfaces of the gearbox case and use a light coat of Loctite 5203 sealant. Assemble the case and start all of the 19 bolts (I used blue Loctite) lightly snug 3-5 of the bolts and reinstall the dowel pins in the case. Using a cross pattern tighten the case bolts to 19-22ft/lbs.

Re install the torque arm mounting bracket.
Install the gearbox and refill with oil. I recommend the original FORD transmission fluid but have also used Red Line MTL with good success.
This thread will be sticky'd until it is submitted into the Official How-To Archive.